How to Clean the Three-Way Catalytic Converter with Oxalic Acid?
3 Answers
Method for cleaning the three-way catalytic converter with oxalic acid: 1. Use a lift to raise the vehicle to the normal working height; 2. Remove the three-way catalytic converter from the vehicle; 3. Prepare oxalic acid solution using specialized maintenance equipment; 4. Soak the three-way catalytic converter in the prepared oxalic acid solution; 5. Rinse off any residual oxalic acid solution and impurities with clean water. The function of the three-way catalytic converter is to convert harmful gases such as carbon monoxide, hydrocarbons, and nitrogen oxides emitted from vehicle exhaust into harmless carbon dioxide, water, and nitrogen through oxidation and reduction reactions. It is an important external purification device installed in the vehicle's exhaust system.
I've actually used oxalic acid to clean a catalytic converter once, and found it quite effective. First, remove the converter from the exhaust pipe—this step requires some tools, so be careful not to force it and damage the connections. Next, prepare the oxalic acid solution; I used oxalic acid powder mixed with water at a ratio of about 1:10 (one part oxalic acid to ten parts water). Warm water helps dissolve it faster. Soak the converter in the solution for about half an hour, watching as the deposits dissolve. Make sure to wear gloves and goggles during this process, and ensure good ventilation to avoid inhaling fumes. After soaking, rinse the converter thoroughly with water to remove any residual acid, then let it dry before reinstalling it on the car. After cleaning, test driving showed smoother exhaust flow and noticeable power recovery. The key to the whole process is proper protection and thorough rinsing—oxalic acid is highly corrosive, and improper handling can damage parts. Occasional cleaning can extend the converter's lifespan, but doing it too frequently might actually accelerate wear.
I think using oxalic acid to clean the catalytic converter should be done with caution. Oxalic acid is a strong acid, and improper use may corrode the precious metal coating inside the converter, affecting its emission function or shortening its lifespan. Personally, I recommend not attempting a DIY unless you're knowledgeable or experienced. It's better to visit a professional auto repair shop—they have specialized cleaning machines and safe solvents, and they can also check for other exhaust system issues. If you must do it yourself, ensure good ventilation, wear protective gear, avoid overly concentrated solutions, and thoroughly test the functionality after rinsing. A clogged catalytic converter can indeed cause poor fuel economy and reduced power, but cleaning is only a temporary fix. The root causes are often engine carbon buildup or fuel quality, so regular maintenance is more crucial.
